International Journal of Contemporary Surgery

Volume 10 No. 2, July-December 2022

Surgical Anatomy of Anterior Abdominal Wall: Know before you Incise

Archana Mishra¹, Nupur Anand²

¹Associate Professor, ²Senior Resident, Department of Obstetrics and Gynecology,

VMMC and Safdarjung Hospital

How to cite this article: Archana Mishra, Nupur Anand. Surgical Anatomy of Anterior Abdominal Wall: Know
before you Incise. International Journal of Contemporary Surgery 2022;10(2):8-15.

Abstract

Incision and closure of the abdominal wall is among the most frequently performed surgical procedures. Anterior
abdominal wall is the first structure which a surgeon encounters in any abdominal surgery. Both in open surgery
and laparoscopic surgery, correct knowledge of layered structure of the anterior abdominal wall is a must to enter
the abdominal wall with maximum efficacy and safety. Hence knowledge of all structures which one encounters
on entering abdominal wall layer by layer is essential for surgeon. Here we discuss in detail about anatomy of
abdominal wall and different types of incisions.

Keywords: abdominal wall, anatomy, incision

Introduction • Posterolateral border : Lumbar spine and its

adjacent muscles
Incision and closure of the abdominal wall is
among the most frequently performed surgical Layers of abdomen :
procedures.  Anterior abdominal wall is the first Skin and Subcutaneous Tissue :
structure which a surgeon encounters in any
abdominal surgery. Both in open surgery and Skin : Dermal layer has fibres which are oriented
laparoscopic surgery, correct knowledge of layered in a predominantly transverse direction. In the lower
structure of the anterior abdominal wall is a must to part fibres have a subtle curving concave upward line.
enter the abdominal wall with maximum efficacy and Surgical Importance :There is more tension
safety.1 on the skin of a vertical incision and it results in a
Anatomy wider scar and more chances of wound dehiscence.
Transverse scars with gentle curve with cephalic
Boundaries of abdominal cavity concavity are more cosmetic. Placing the incisions
• Superior border : lower edge of the rib cage in the pubic hair line or in a natural skin crease may
(ribs 7 through 12). enhance the cosmetic result. Avoid incision in deep
• Inferior border : Iliac crests, inguinal skin fold of a large panniculus where maceration of
ligaments, and pubic bones. the skin can increase the risk of infection.

Corresponding Author: Nupur Anand, Senior Resident, Department of Obstetrics and Gynecology, VMMC
and Safdarjung Hospital, New Delhi.

E-Mail: nupur28@yahoo.co.in
 [b]Subcutaneous Tissue : Subcutaneous tissue is above the symphysis.
made of globules of fat which are held in place and
Surgical Importance: Strong attachment of
supported by a series of branching fibrous septa.
pyramidalis to the midline makes separation of their
There are two fascias in saubcutaneous tissue:
attachment difficult by blunt dissection.
• Camper’s Fascia : Camper’s fascia is the more
superficial portion of the subcutaneous layer Flank Muscles
where fat predominates, and the fibrous Lateral to vertical muscles are the flank muscles:
tissue is less apparent. the external oblique, internal oblique, and transverse
• Scarpa’s fascia: It is closer to the rectus abdominal. External oblique is most superficial of all
sheath where the fibrous tissue predominates flank muscles. Its fibers run obliquely anteriorly and
relative to the fat. Scarpa’s fascia is not seen as inferiorly from their origin on the lower eight ribs
a well-defined layer during vertical incisions. and iliac crest. It’s fibres run obliquely downward.
Musculoaponeurotic Layer Internal Oblique muscles : fibers of the internal
oblique muscle fan out from their origin in the
Deeper to subcutaneous tissue is the layer of anterior two thirds of the iliac crest, the lateral part of
muscle and fibrous tissue which functions to hold the the inguinal ligament, and the thoracolumbar fascia
abdominal viscera in place and controls movement in the lower posterior flank.
of the lower torso. There are two major groups of
muscles: Surgical Importance : Vertical incisions are more
prone for dehiscence than transverse incisions due
• Vertical muscles
to transverse pull of their attached muscular fibers
• Oblique flank muscles placed in the rectus sheath.

Rectus Sheath [Conjoint Tendon] : Rectus

sheath is the broad, sheet- like tendons of these
muscles which form aponeuroses that unite with their
corresponding member of the other side, forming
a dense white covering of the rectus abdominis
muscle. The conjoined aponeuroses of the flank are
separable lateral to the rectus muscles but fuse near
the midline. Rectus sheath in its lower one fourth
lies entirely anterior to the rectus muscle. Above that
point, it splits to lie both ventral and dorsal to it. The
transition between these two arrangements occurs
midway between the umbilicus and the pubes and is
called the arcuate line. Cranial to this line, the midline
ridge of the rectus sheath, the linea alba, unites these
two layers. Linea Alba (the white line) is completely
avascular. The lateral border of the rectus muscle is
Vertical Muscles
marked by the semilunar line of the rectus sheath.
Vertical muscles are the rectus abdominis muscle During a transverse lower abdominal incision, the
which is found on either side of the midline and external and internal oblique aponeuroses are often
pyramidalis muscle which is located just above the separable near the midline.
pubes. Rectus abdominis muscle originates from the
Surgical Importance : Linea alba is the preferred
sternum and cartilages of ribs 5th to 7th and inserts
location for incision and intra-abdominal access in
into the anterior surface of the pubic bone. The
emergency. Due to lack of muscular coverage this
pyramidal muscles arise from the pubic bones and
area is weak and incisions are prone for the formation
insert into the linea alba in an area several centimetres
of the majority of post-surgery ventral hernias.
 Archana Mishra, Nupur Anand / Surgical Anatomy of Anterior Abdominal Wall: Know before you Incise. 10

Transversalis Fascia, Peritoneum, and Bladder muscular branches and anterior perforating branches
Reflection supplying skin and subcutaneous tissues.

The peritoneum is a single layer of serosa Inferior epigastric arteries : Inferior epigastric
supported by a thin layer of connective tissue that arteries  are the branches of the external iliac artery.
lines the abdominal cavity. Five vertical folds are The inferior epigastric artery and its two veins
formed by underlying ligaments or vessels that originate lateral to the rectus muscle. They run
converge at the umbilicus. diagonally toward the umbilicus. These intersect the
muscle’s lateral border midway between the pubis
• The abdominal wall reflection of the bladder,
and umbilicus. Below the point at which the vessels
which fuses with the urachus
pass under the rectus, they are found lateral to the
• The single middle umbilical ligament (the
muscle deep to the transversalis fascia.
obliterated urachus)
• The paired medial umbilical ligaments Surgical Importance : The inferior epigastric
(remnants of the obliterated umbilical vessels are bounded only by loose areolar tissue below
arteries) the arcuate line. Trauma to this portion of the deep
• Lateral umbilical ligaments associated with inferior epigastric artery may result in considerable
the deep inferior epigastric vessels hemorrhage. Hematomas commonly dissect into
the retroperitoneal space, large quantities of blood
Surgical Importance :
may be lost before outward evidence of hematoma
• Bladder reflection is frequently incised or is detectable.
bluntly dissected off the bladder to take the
• Lateral laparoscopic trocars are placed in a
tissues in this region “down by layers”.
region of the lower abdomen where injury
• During laparoscopy lateral umbilical to the inferior epigastric and superficial
ligaments should be localised to prevent epigastric vessels may occur.Laparoscopic
injury to deep epigastric vessels during surgeon should know the average location of
secondary port placement. these blood vessels which helps in choosing
• Paired medial umbilical ligaments insertion sites that will minimize their
are important landmarks during injury and the potential hemorrhage and
laparoscopy for pelvic surgery. hematomas that this injury can cause.
• Surface marking of these vessels is just above
Vasculature3
the pubis symphysis, inferior epigastric
The blood supply of the abdominal wall is vessel and superficial epigastric vessels lie
comprised of superficial and deep vascular supplies. approximately 5.5 cm from the midline,
whereas at the level of the umbilicus, they
Superficial arteries : The superficial vasculature are 4.5 cm from the midline. Trocars should
is located in the subcutaneous tissues and supplies the be placed lateral to it.
tissues superficial to the external oblique aponeurosis • Control of bleeding of superficial vessels:
and the anterior rectus sheath. The muscles and
• Smaller vessel in subcutaneous tissue
tissues below these layers are supplied by the deep
constrict by itself but persistently bleeding
vessels that are located in the musculofascial layers.
vessels should be managed with limited use
Deep arteries of electrocautery.
• Control of bleeding from Inferior epigastric
Superior epigastric arteries  : The superior
vessels: It is best accomplished by isolating
epigastric artery is a terminal branch of the internal the vessel through dissection, clamping it
thoracic artery. Deep branches of this vessel supply with a hemostat, and suture ligating it at
the posterior rectus sheath and the peritoneum with both torn ends.
11 International Journal of Contemporary Surgery / Volume 10 No. 2 July-December 2022

and transversus abdominis muscles to target

the nerves passing through them. It provides
good postoperative pain relief.

Nerve Supply : The skin and muscles of the

anterolateral abdominal wall are supplied by T7 to
T12 and L1 spinal nerves. The iliohypogastric and
ilioinguinal nerves pass medial to the anterosuperior Lymphatics Drainage :   Superficial lymphatics
iliac spine in the abdominal wall. Ilioinguinal nerves above the umbilicus pass in a superior direction to
supplies the lower abdominal wall, and by sending the axillary nodes, below the umbilicus passes in an
a branch through the inguinal canal, it supplies inferior direction to the superficial inguinal nodes.
the upper portions of the labia majora and medial
portions of the thigh. Incisions on Anterior Abdominal Wall

Surgical Importance :4 Choice of incision — Points to be taken care while

choosing an incision :5
The genitofemoral (L1 and L2) and
femorocutaneous (L2 and L3) nerves can 1. Provide adequate exposure for the
be injured during gynecologic surgery if anticipated procedure.
transverse skin incision goes more laterally. 2. Taking into account the possibility that
the planned procedure may change
• Genitofemoral and femorocutaneous nerves depending upon intraoperative findings or
can be entrapped in the lateral closure of a complications.
transverse incision and may lead to chronic
pain syndromes. 3. Should interfere minimally with abdominal
wall function by preserving important
The femoral cutaneous nerve can be compressed abdominal structures.
either by a retractor blade lateral to the psoas or by 4. Should heal with adequate strength.
too much flexion of the hip in the lithotomy position,
causing anesthesia over the anterior thigh,diminished Other factors guiding incision
knee jerk, and weakness of extension of the knee, • Need for rapid entry
which creates a specific problem climbing stairs. • Certainty of the diagnosis
• Genitofemoral nerve lies on the psoas muscle. • Body habitus
During prolonged surgery where pressure • Location of previous scars
from a retractor can damage this nerve.It
leads to anaesthesia in the medial thigh and • Potential for significant bleeding
lateral labia. • Minimizing postoperative pain
• The “Transverse Abdominis Plane [TAP] • Cosmetic outcome
“Block is a peripheral nerve block designed to
Scalpel versus Electrosurgery for incision6
anesthesize the nerves supplying the anterior
abdominal wall [ T6 to L1] by deposition of Neither scalpel nor electrosurgery holds a
local anesthetic between the internal oblique significant benefit over the other. However, use of
 Archana Mishra, Nupur Anand / Surgical Anatomy of Anterior Abdominal Wall: Know before you Incise. 12

electrocautery for incision is associated with lower 5. Turner -Warwick’s incision

postoperative analgesic requirements. With use of
scalpel a surgeon should not practice multiple strokes
which result in greater tissue damage and increase
the susceptibility to infection. 

Types of incisions for a pelvic surgery:

There are generally two main types of incision:

longitudinal and transverse/oblique.

However. data strongly supporting one incision

over another are lacking, the choice of incision
remains the preference of the surgeon.
Longitudinal Incisions:
1. Midline incision
Oblique Incisions:
2. Paramedian incision
3. Lateral paramedian incision 1. McBurney’s incision
4. Pararectal incision 2. Subcostal incision
3. Thoracoabdominal incision

Mostly low transverse incisions and midline

Transverse Incisions : incisions are used in gynaecology.
1. Pfannenstiel’s incision
Advantages and disadvantages of both these
2. Cherney’s incision
incisions are given below :7
3. Maylard’s incision
4. Kustner’s incision
13 International Journal of Contemporary Surgery / Volume 10 No. 2 July-December 2022

Transverse Incision Midline Incision

Advantages More suited in planned surgery More suited in emergency or if diagnosis or location
Less wound dehiscence of bleeding is uncertain

Cosmetic Most rapid entry, suited patients in shock or sepsis

Lower incidence of adhesion More exposure to upper abdomen

formation and postoperative bowel Extensibility if need arises
obstruction  Midline incision is associated with less bleeding
Less painful and have less impact and less potential for nerve injury
on pulmonary function compared
to a longitudinal, midline
incision, particularly in the early
postoperative period.
Lower incidence of incisional
hernias
Disadvantages Limited exposure provided to the More wound dehiscence and hernia
upper abdomen Cosmetically less satisfactory
Limited extensibility More analgesia use
Increased surgical time More pulmonary compromise
Relatively larger blood loss
Problematic if the pannus is large.
Paramedian incision:  A paramedian incision is anterior rectus sheath, which is incised transversely.
made 2 to 5 cm to the left or right of the midline. The upper and lower fascial edges are grasped and
elevated with a heavy toothed clamp and dissected
Advantage : Less chances of dehiscence or hernia
bluntly and sharply off the underlying rectus muscle
and extensibility.
from the umbilicus to the symphysis. The rectus
Disadvantages: muscle is separated along the midline raphe, exposing
the transversalis fascia. Posterior rectus sheath is
• Longer time to perform
separated above the arcuate line. Peritoneum is incised
• Restrict access to the contralateral pelvis vertically taking care of underlying structures. In
• More injury to the epigastric vessels this incision sheath is closed with continuous suture.
• Nerve injury may result in rectus paralysis Skin is approximated with a subcuticular (SC) suture.
and rectal atrophy Fascia is closed with continuous delayed- absorbable
• More difficult closure than midline suture. Subcutanous tissue has to be closed if > 2
cm depth. Skin is approximated with subcuticular,
Transverse Incisions : Commonly used Transverse absorbable monofilament suture
incisions in gynaecology are:
Advantages : It provides excellent strength and
[1] Pfannenstiel’s incision : It is most commonly cosmesis, and exposure is adequate for procedures
used in gynaecology. It is a muscle-separating limited to the pelvis.
operation.
Disadvantages:8
Indication : When pathology is strictly confined
to pelvis only. • Speed of entry is restricted and the risk of
seroma, hematoma, and wound infection
Technique : It is placed 2 to 5 cm above the pubic may be increased.
symphysis and usually is 10 to 15 cm in length. After • If the incision is extended beyond the rectus
the skin is entered, the incision is carried up to the muscle, the iliohypogastric and ilioinguinal
 Archana Mishra, Nupur Anand / Surgical Anatomy of Anterior Abdominal Wall: Know before you Incise. 14

nerves may be traumatized, and some • In patients with significant aortoiliac

patients will experience chronic pain  due occlusion, blood supply to lower limbs
nerve entrapment and neuroma formation. is dependent on collateral flow from the
• In men, risk of inguinal hernia is more when epigastric vessels. Maylard incision may
the incision is close to the external inguinal result in leg claudication and even acute leg
ring. ischemia.
[2] Cherney’s incision : [4] Kustner’s incision: Kustner’s incision is a
Technique : Cherney’s incision is similar to the transverse skin incision approximately 5 cm above
Pfannenstiel incision except it is placed is placed the symphysis and just below the anterior iliac spine.
slightly lower on the abdomen and involves incising
Technique : After skin subcutaneous tissue is
the rectus tendons leaving only half centimetre of it for
separated from the rectus sheath in a vertical plane
reattachment. The muscles and tendons are retracted.
to reveal the linea alba. Numerous small branches
and the peritoneum is incised longitudinally. Closure
of the superficial epigastric plexus of vessels may
of incision requires reattachment of the muscle
be encountered and must be ligated to prevent
tendons to their insertions. This is usually done
excess oozing. Care must be taken to dissect only
by using permanent horizontal mattress sutures.
enough to expose the linea alba and not to separate
Alternatively, the tendons of rectus muscle may be
attached to the lower rectus sheath. the subcutaneous tissue too far laterally. A vertical
midline incision is then made in the linea alba.
Advantage : Cherney’s incision provides excellent
exposure to the retropubic space of Retzius. It is Advantage : It was developed to reduce the risk
preferred for retropubic urethropexy. Sometimes a of evisceration and for good exposure. Risk of hernia
pfannenstiel incision may be converted to a Cherney and wound dehiscence is less.
incision to enhance exposure during surgery. Risk of
Disadvantage :
hernia is also less.
• Very time consuming because of the need for
[3] Maylard’s incision  [Mackenrodt incision]:9
extensive hemostasis.
It is a transverse incision at the level of the anterior
iliac spine. • It has disadvantages of both midline and
transverse incisions and therefore has limited
Technique : Before transection of the muscles, utility and no extensibility.
the deep inferior epigastric vessels are identified on
• Collection of blood and serum increases
their lateral undersurface. The vessels are isolated,
the risk of infection and may necessitate
clamped, transected, and ligated. During transection
of the rectus muscles, dissection from the anterior drainage. Risk of hernia is equal to midline
rectus sheath should be avoided in order to limit incision.
retraction of the muscles. In addition, the cut edge Turner-Warwick’s incision : Turner-Warwick’s
of the muscle may be secured to the anterior sheath incision is centered 2 to 3 cm above the symphysis
with 0-caliber absorbable mattress sutures to further and placed within the lateral borders of the rectus
prevent retraction. muscles.
Advantage : Adequate abdominal and pelvic
Trocar placement in laparoscopy : During trocar
exposure for complex gynaecologic surgery.
placement Ilioinguinal and iliohypogastric nerves,
Disadvantage : superficial and inferior epigastric arteries to be taken
care to avoid injury. The lower quadrant ports are
• Access to upper abdomen is limited.
placed approximately 2 cm medial and at or superior
• Delayed bleeding from the cut edge of the
to the anterior superior iliac spine, lateral to the
rectus muscle or deep epigastric vessels can
border of the rectus muscle.10
occur.
15 International Journal of Contemporary Surgery / Volume 10 No. 2 July-December 2022

Conclusion 4. Whiteside JL, Barber MD, Walters MD, Falcone T.

Anatomy of ilioinguinal and iliohypogastric nerves
All gynaecologist should be well versed with in relation to trocar placement and low transverse
anatomy of anterior abdominal wall. As the famous incisions. Am J Obstet Gynecol 2003; 189:1574.
saying goes “Pray before surgery, but remember : 5. Meeks GR, Trenhaile TR. Management of abdominal
God will not alter a faulty incision. incisions. J Pel Surg 2002; 6:295.
Conflict of Interest : none 6. Ahmad NZ, Ahmed A. Meta-analysis of the
effectiveness of surgical scalpel or diathermy in making
Source of Funding : none abdominal skin incisions. Ann Surg 2011; 253:8.
Ethical Clearance : none 7. Brown SR, Goodfellow PB. Transverse verses midline
incisions for abdominal surgery. Cochrane Database
References Syst Rev 2005; :CD005199.

1. Flament JB. [Functional anatomy of the abdominal 8. Loos MJ, Scheltinga MR, Mulders LG, Roumen RM.
wall]. Chirurg 2006; 77:401. The Pfannenstiel incision as a source of chronic pain.
Obstet Gynecol 2008; 111:839.
2. Wong VW, Bhatt KA, Vial IN, et al. Beyond Langer’s
Lines: Manipulating wound mechanical forces to 9. Giacalone PL, Daures JP, Vignal J, et al. Pfannenstiel
control hyperochic scar formation in the red Duroc versus Maylard incision for cesarean delivery: A
pig. J Am Coll Surg 2010; 211:S77. randomized controlled trial. Obstet Gynecol 2002;
99:745.
3. Rozen WM, Ashton MW, Taylor GI. Reviewing the
vascular supply of the anterior abdominal wall: 10. Whiteside JL, Barber MD, Walters MD, Falcone T.
redefining anatomy for increasingly refined surgery. Anatomy of ilioinguinal and iliohypogastric nerves
Clin Anat 2008; 21:89. in relation to trocar placement and low transverse
incisions. Am J Obstet Gynecol 2003; 189:1574.